The present disclosure relates to push-and-turn child-resistant packages of the type in which internal lugs on a closure skirt are received in pockets on the undersides of external projections on the container neck finish, and in which the closure is biased by one or more spring elements to retain the lugs in the pockets. Axial pressure on the closure against the force of the spring element(s) and simultaneous turning of the closure with respect to the container permits removal of the closure from the container neck finish. Packages of this type conventionally are employed for prescriptions, vitamins and other medications, and for a number of other applications such as laundry products. See, for example, U.S. Pat. Nos. 4,057,159, 4,059,198 and 4,485,932. The present disclosure relates to improvements in such packages, and to closures and containers for such packages, that facilitate automated application of the closure to the container neck finish.
The present disclosure embodies a number of aspects that can be implemented separately from or in combination with each other.
A child-resistant package in accordance with one aspect of the present disclosure includes a container having a neck finish with an open mouth, an angularly spaced array of external projections with notches on undersides of the projections, and a conical internal surface around the mouth. A closure has a base wall, a first annular wall with angularly spaced internal lugs received within the notches, and a second annular wall disposed radially inwardly from the first annular wall and in resilient sealing engagement with the internal surface on the container neck finish. The second annular wall has a substantially cylindrical portion adjacent to the base wall and a conical portion extending from the cylindrical portion at an angle inwardly from the first annular wall and away from the base wall. The conical portion of the second annular wall has an edge remote from the base wall that is spaced from the internal surface of the container neck finish. This angulated free edge of the second annular wall helps prevent interference between the second annular wall and the container mouth during automated application of the closure to the container neck finish.
A child-resistant closure in accordance with another aspect of the disclosure includes a one-piece molded plastic shell having a base wall, a first annular wall with angularly spaced internal lugs and a second annular wall disposed radially inwardly from the first annular wall. The second annular wall as molded has a cylindrical portion adjacent to the base wall, and a conical portion extending from the cylindrical portion and at an angle inwardly from the first annular wall and away from the base wall. The internal lugs on the first annular wall preferably have convex radially inwardly facing surfaces. Each of these surfaces has a clockwise edge and a counterclockwise edge as viewed from the base wall of the closure. The clockwise edge of the surface preferably is closer than the counterclockwise edge to an inside surface of the first annular wall. The radially inwardly facing surface of each lug preferably has a first portion with a uniform radius of curvature from the clockwise edge to a position adjacent to but spaced from the counterclockwise edge, and a second portion that is flat from said first portion to said counterclockwise edge. This lug surface configuration facilitates automated application of the closure to a container neck finish.
A molded plastic container in accordance with a further aspect of the present disclosure includes a neck finish having an open mouth, an angularly spaced array of external projections with notches on undersides of the projections, and a conical internal surface around the mouth. The conical internal surface has a first portion adjacent to the mouth and a second portion extending from the first portion. The second portion is at an angle greater than the first portion with respect to an axis of the container neck finish. This surface configuration is adapted to cooperate with a spring/seal wall on the closure to bias the closure away from the container neck finish when the closure is over-applied to a container neck finish.